1. Field of the Invention
The present invention relates to an apparatus for enclosing the electronics used to monitor variables in food processing systems. More particularly, the present invention relates to an enclosure for protecting the electronics used in a food processing system from the harsh environmental conditions present in such systems.
2. Description of Related Art
The food industry produces a large quantity of standardized food products. In order to control the processes used to make standardized food products the industry is relying to a greater extent on electronic control systems which monitor various food manufacturing processes and input variables in order to control the quality of the food product as well as to minimize waste and decrease costs.
One difficulty in using sophisticated electronic circuitry in a food processing plant is the harsh environment present in such facilities. Food processing facilities such as poultry processors must wash and disinfect equipment used to manufacture poultry products with hot water at high pressures. A typical plant is cleaned using water at approximately 130-140 degrees Fahrenheit. Because the plants are often refrigerated to temperatures in the range of 38-45 degrees Fahrenheit, at lest in sections, certain of the electronic components are subject to significant thermal shocks when sprayed with the hot water during the cleaning process. Such thermal variations also result in condensation in standard electronics enclosures which would ultimately damage the electronics components.
An additional problem is created by the high pressure of the water used to clean the equipment. Water at more than 600 psi is often used to clean the food processing equipment near which the electronic monitoring and control systems must be located. Such water pressures can easily penetrate currently available electronics enclosures resulting in damage to the electronic circuitry therein.
Another hostile component of the food processing plant is the food being processes. Particles of food and fluids can lodge in hinges, crevices, seams, grooves, fittings, exposed threads and blind holes common on typical electronics packaging.
Due to the importance of the control and monitoring electronics in the production of high-quality standardized food products, the electronics cannot be removed for servicing without disrupting production. Presently available enclosures require the electronics and the enclosure be removed for servicing.
To date there is no electronics enclosure used in the food processing industry which will provide the necessary protection from water, water vapor, thermal heat transfer shock, condensation, and other problems described above.
U.S. Pat. No. 5,603,892 to Grilletto et al. provides for a gas purged electronics enclosure in which a control system is used to open and close valves in order to purge oxygen and water vapor from an electronic circuit package. This reference does not address the problems of thermal shock and also provides a more complex and expensive solution than the present invention.
In light of the foregoing, there is a need in the art for an electronics enclosure which is capable of withstanding the harsh environmental conditions present in the food processing plant while simultaneously permitting easy access to the electronics stored within.